header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 50px;
    background-color: #29BDE0;
    border-bottom: solid 1px #74d4eb;
    z-index: 1;
    overflow: hidden;
    .back {
        width: 15px;
        height: 15px;
        margin-left: 20px;
        border-top: 3px solid #ffffff;
        border-right: 3px solid #ffffff;
        transform: rotate(225deg);
        cursor: pointer;
    }

    .font {
        font-size: 20px;
        color: #ffffff;
        letter-spacing: 5px;
    }

    .close {
        display: inline-block;
        margin-right: 30px;
        width: 2px;
        height: 30px;
        transform: rotate(45deg);
        background: #ffffff;
    }
    .close::after{
        content: "";
        display: block;
        width: 2px;
        height: 30px;
        transform: rotate(-90deg);
        background: #ffffff;
    }
}